Magnetic clutch.



PATENTED JAN. 7, 1908.

T. S. WATSON. MAGNETIC CLUTCH.

APPLICATION FILED APR.1,1907.

- 'rnomas s. WATSON, F MILWAUKEE, Wisconsin.

IAGNI'I'IC CLUTCH.

- Specification of Letters Patent.

Patented rm. '1, 1908.

Application and ,111 1. 1907. Serial-Io. 365.642.

4 To all'whom it may concern:

Be it known that I, THOMAS S. WA'rsoN,

residing in Milwaukee, in the count. of Milwaukee and .State of Wisconsin, ave invented new and-useful 'Im rovements in Magnetic Clutches,of which t e following is adescription, reference bein had to the accompanyrng drawings, whic are a part of this specification.

This invention has for its object to provide a clutch for coupling-a driving part with .a dnven' part by c electro magnet and thereby cause the engage ment of a member of the driving part with the driven part and through the resulting torsion oduce the expansion or contraction of a 001 member carried by the part and cause it to frictionally engage the iven art.

[Another object ,of this invention is to improve upon details ofconstruction of a magnetic clutch of this t I e.

With the above .an other objects in view the invention consists in the magnetic clutch herein claimed, its parts and combinations of parts and all equivalents.

Referrin to the accompanying drawings in which I e characters of reference indicate the same parts in the different views; Figure 1 is a central sectional view of a ma netic clutch constructed in accordance wit this invention; and, Fig. 2 is an end elevation thereof wlth parts broken away for-clearness of illustration. 7

In these drawings 5 re resents a driving shaft, which may be the s aft of an electric motor .or any other suitable driving means, and 6 is a sleeve mounted thereon and rigidly locked thereto at one .end by a set screw 7 passing through a collar 8 around the sleeve and 'throu h the, said sleeve and into .the shaft ,5]. 'l he sleeve 6 is preferablyof phosphor-bronze or other suitable sprin metal and is provided with a s irally cut s 01; 9 by means of'which the middle portion becomes a spiral or coil spring.

cylindrical casing 10 with an inner cy1in dries-l portion and one closed end is loosely fitted onthe sleeve 6 and against the collar 8 and constitutes a driven member in the form of a belt pulley with a flange 11 for guiding the belt. The casing 10 a so constitutes a housi or receptacle for a magnet coil 12 aroun the inner cylindrical portion as a core, the terminals 13 and 140i which pass through insulating bushings in the closed end osing a circmt through anotherwise conveniently located has an insu-.

lating arm 19 adjustably mounted thereon and carrying spring pressed brushes 20 engaging the respective collector rings 1.5 and 16, said brushes being connected .by wires .21

with a suitably controlled source of whereby the ma 1 Ply et may be energized and' denergized by c osing and opening the circuit therethrou h m any suitable manner convenient for t e operator.

The open end of the casing 10 is covered by an armature or engaging member 22 which is secured by a key 23 to the free end of sleeve 6 and which has a ta ering engaging surface 24 with the end of t e casing, its outer edge 25 forming the other flange for the belt pulley. A ring 26 of brass or other non-maglnetic material is fitted to the ,open

end of t e casing 10 to keep the magnet coil 12 in place and protect it from injury, and I spring, pressed pins 27 are located in the mature member 22 to bear against the inner or core dportion of the casing IO-for normally hol mg the armature member awayl from the cas' A nut 28 is threaded on t e free end of t e sleeve 6 and engages the armature member 22 to securely hold it in place.

A lubricating cup 29 is secured to the end of the shaft and communicates through an angular bore 30 thereof with the surface of the shaft where it is surrounded by the C01l spring portion of sleeve 6.

In operation, when the circult through the magnet is broken the shaft 5 or the driv ng part is free to turn independent of the belt pulley or driven (part so that any suitable mechanism belte to the belt pulley may remain idle during the operation of the motor or other driving mechanism. This is per; mitted by reason of thefact that the sleeve 6. is then entirely loose within the bore of casin 10 and the armature member 22 is held by the spring ins .27 out of contact with said casing. Vshen, however, the circuit iscompleted through the magnet the magnet becomes energized and attracts the armature member 22 into engagement therewith at the beveled engaging surface 24, this engagement tending, to retard the rotary movement of the armature member and and the bore of't e casing is of great bindingforce and is suflicient to com letely lock the belt pulley with the shaft an thereby cause the mechanism belted to the pulley, to be driven by the motor. As soon as the circuit through themagnet is interrupted the spring pins 27 disengage the armature member 23 cm the casing and the coil spring portion of the sleeve 6 is thereby permitted to naturally contract'to its normal size and release 1 its engagement with the bore of the casing.

' the coil spring,

The lubricant cup supplies lubricant to all of the working parts and avoids undue wear thereof. L I

Obviously parts may be reversed so that the magnet is carried by the engaging member or the coil sprin may be caused to contract in order to pro uce the clutching action and various other changes may be made without departing from the spirit and scope of this invention.

What I claim as my invention is;

1 A magnetic clutch, comprising a driving shaft, a coil spring secured thereto at one end, a member secured to the other end of a driven member loosely mounted around the coil spring and normally out of engagement with the other member, and an electro magnet for attracting the driven member and the other memher to each other to retard the movement of.

the said other member and thereby cause the expansion of the coil spring into frictional engagement with the driven member.

2. A magnetic clutch, comprising a driving shaft, a coil spring mounted thereon and secured thereto at one end, an engaging member secured to the other end of the coil spring, a driven member loosely mounted on the coil spring, spring pressed pins for holding the engaging member normally out of engagement with the driven member, and an electro magnet for attracting the driven member and the engaging member to each other to retard the movement of the engaging member and thereby cause the expansion of the coil s ring into frictional engagement with the riven member, the spring pressed pins serving to disengage the engaging member from the driven member and'permit' the .coil spring to contract and release the driven-member when the magnet is denergized 3. A ma etic clutch, comprising a driving shaft, a coil spring mounted thereon and secured thereto at one end, an engaging member secured to the other end of the coil spring, a driven member loosely mounted on the coil spring and having a tapering engaging fit with the engaging member, means for holding the engaging member normally out of engagement with the driven member, and an electro magnet for attracting the driven member and the engaging member to each other to retard the movement of the engaging member and thereby cause the expansion of the coil spring into frictional engagement with the driven member, said means serving to disengage the engaging member from the driven member and permit the coil spring to ,contract and release the driven member when the magnet is deenergized.

4. Amagnetic clutch, comprising a driving shaft, a sleeve mounted thereon and secured at one end thereto, there being a s iral slot in the sleeve forming a coil spring 0 the intermediate portion thereof, a driven member comprising a casing loosely mounted on the sleeve around thecoil spring' portion thereof, an electro magnet contained within the casing, an armature member secured to the other end of the sleeve and adapted to be at tracted by the magnet into engagement with the casing for retarding the movement of the armature member and causing the coil spring ortion of the sleeve to unwind and expand. into frictional engagement with the'casing,

and spring means for disengaging the armature member from the casing when the magnet is deenergized and permitting the coil spring portion of the sleeve'to contract and 4 release the casing.

5, A magnetic clutch, comprising a driving shaft, a sleeve mounted thereon and secured 4 at one end thereto, there being a spiral slot in the sleeve forming a coil spring of the intermediate portion thereof, a driven member vcomprisin a cylindrical casing with'acon- -centric cy 'ndrical portion loosely mounted on the sleeve around the coil spring ortion thereof, a magnet coil contained wit 'n the casing around the inner portion as a core, a pair of collector rings mounted on the casing and connected with the terminals of the magnet coil, brushes engaging the collectorrings, a collar mounted on the sleeve against which the casing bears, an armature member keyed to the free end of the sleeve, there being-pa tapering engaging surface between the armature member and the outer cylindrical portion of the casing, flanges on the casing and the armature member for guiding a belt on the casing as a belt pulley, a ring seated in the end of the casing and protecting the magnet coil, spring pins slidably mounted in the armature member and bearing on the casing for normally holding the armature member out of engagement with the casing, and a lubricant cup mounted on the driving shaft -and having communication with the surface thereof within the coil spring portion of the sleeve; 7

' 6. A magnetic clutch, comprising a driving member, a coil spring connected therewith, a driven member adapted to be engaged by the coil spring when. torsional stress is exerted thereon, an engaging member connected with the coil spring, an electro magnet for attracting the driven member and the engaging member into engagement with each other, and means for normally holding the driven member and the engaging member apart.

7. A magnetic clutch, comprising a driving member, a coil spring connected therewith, an engaging member connected with the coil spring and moved thereby, a driven member adapted to be engaged by the coil spring when the movements of the engaging member are retarded, an electro magnet for causing an engagement between the driven mem- 15 mally preventing engagement between the 20 engaging member and the driven member.

In testimony whereof, I aflix my signature, lIl presence of two witnesses.

THOMAS S. WATSON.

Witnesses:-

R. S. CALDWELL, ANNA F. SOHMIDTBAUER. 

